Speed-responsive device



Nov. 17,1925. Y

w. RAYMOND SPEED' RESPONSI VE DEVICE Filed seht. 26. 192s Patented Nov. 17, 1925.

STATES' I 1,561,835- PATENT Y oFFlacfE.'

WARD RAYMOND, 0F EASTON, PENNSYLVANIA, A-SSIGNOR T0 PENNSYLVANIA PUMP"&-'GOMPRESSOR COMPANY, 0F EASTON, :PENNSYLVANIA,r A CORPORATION or" PENNSYLVANIA.

SPEED-RESPONSIVE DEVICE.

vApplication led September 26, 19.23. Serial No. 664,942.l

ToaZZ whom t mayI concern Be it known that I, WARD RAYMOND, a citizen of .the United States, residing at Eastominthe countyl of Northampton and State lof `lennsylvania, Ahave invented certain-new and useful Improvements in Speed- Responsive Devices, of which the following is a speci-cation. c

.Thisinventionrelates particularly to speed responsivedevices and tor such devices used asunloaders for compressors.

An obj/ect of the invention is to provide an unloader which will. maintain the comfpressor in its unloaded condition until the speed reaches approximately normal. l

The above and other objects are. accomplished by providing .a :member preferably on the fly wheel'l and main or fly wheel shaft:

ofa compressor or other element and movable under the influences of the centrifugal forces set up as the compressor attains its normal speed. Y V

.Another object of the inventionv is to act-nate the unloader .byy means of a pilotvalve through the centrifugal speed responsive device so that withpressure. in the receiver the compressor is ,prevented from discharging fluid into the receiver until. the speed of thecompressor approachesnormal. Also, assoon as this. speed is reached, the pilotl valveisclosed, thus releasing the pressure of the fluidv in the unloading devices and starting operation of the compressor.

Another object'ofthe inventiony is to provide special attaching means for the centrifugal weightfby means of which the unloader is actuated.

:Preferably these means. comprise a plu.- rality of links so mounted that they may swing aboutparallel .axesv and. move the weight attached to 4their outer ends in an axial direction as it' is moved radially byl the centrifugal force due to its.- rotation..

With these and other objectsin view, my invention consists .in the features of construction and operation set forth. in the following speci'fication; and illustrated in the accompanying drawing.

In the accompanying drawing, I have shown my invention embodied in a .power driven air compresser but it willr be understood that the invention can be otherwise embodied and that ,the drawing: is not to` be construed aswdeining'- or limiting the scope ofthe invention,.the.claims appended to this speci'lication being relied .upon for that pur- Vthe partsin a diiferentoperative position.

In the above mentioned drawing, I have shown but one embodiment of the invention which is now deemed preferable, but it is to be understood that changes and moditications may be made within the scope ofv theappended claims without'departing froml the spirit of the invention.

Briefly, my inventionv in its broadestaspect comprises the followingprincipal parts: first, a compressor adapted to be driven by any suitable source preferably through a belt passing over a pulley provided on a main driving shaft; second, a centrifugal element mounted for radial and axial movement when subjected to centrifugal forces; third, a pilot valv-e adapted to be opened and closed by movement of said centrifugal element; and fourth, controlling. devices for the compressor actuated when the centrifugal element is moved a sufficient distance to force the pilot `valve to its open position.

Referring more in detail to the figures of the drawing, at 10 is: shown the cylinder of a compressor having a main driving shaft 11. On thev shaft 11 are pulleys 12, one of which is .clearly shown in Fig. 1. By mea-ns of a suit-able belt 13 passing around one of the pulleys 12, Vthe shaft 11 may be rotated at any desired-speed. As the connections between the shaft 11 and a piston within cylinder l0 may be of any form, theyv will not require description and have not been shown on the drawing.

As shown in Fig. 2, the huh 15 ,of one of the. pulleys 12 is cut away to form ya suitable bearing for a ring 16. This ring 16 surrounds thecut-away portion of the hub 15 and is-fastened directly thereto by any suitently be described. Pivota-lly mounted on.

posed pins 19 secured within the ring member 16.

The outer ends of these links 18 pivotally lengage an annular extension 2O of a centrifugal elementor weight 21. By reason of its mode of support on the three links which are oscillatory upon parallel axes, the element or weight 21 may move radially relative to the shaft 11 and simultaneously move axially a short distance. A heavy spring 22, the force of which may befjvaried by adjustment of the wing nut 23',` normally' forces the weight 21 to its innermost position. lThe innermost position of the weight 21 is limited by the lug or abutment 1'? formed on the ring member 16. This position of the weight 21 is shown in Fig. 2. From the above description, it will be seen that with rotation of the main shaft 11, the weight 21 will be thrown outwardly against the pressure of spring 22 due to centrifugal forces being set up, and by reason of the obliquefly disposed links 18 will be caused to move axially.

Adjacent the annular portion 2O of the weight 21, which as shown surrounds the shaft 11, is a bell crank 2/1-A pivoted at 25. At the end of one of the arms of this bell crank is a` roller 26 adapted to ride upon the flat radial surface of the annular portion 20. The other arm of the bell crank 24- bears against a rod 27 which enters the body portion 28 of a pilot valve and presses against a ball 29.

The pilot valve body 28 is suitably attached to a portion of the compressor and is provided with a conduit 30 leading from the compressor receiver (not shown) and anl other conduit 31 leading to the compressor controlling devices of the desired form. As shown in Fig. 1, these compressor controlling devices may be relief valves 32 adapted when pressure is admitted to them to form exhaust openings in the opposite ends of the cylinder 10 and prevent any compression taking place while they are open. Also, if desired, a discharge pipe unloader 33 of any conventional or usual type may be provided in the discharge pipe 311 of the compressor which may be operated by fluid means.

The ball 29 previously referred to forms a valve adapted to open or close communication between conduits 30 and 31, and consequently controls the supply of 'linid to the controlling means and 33. .A seat for this valve 29 is formed in the body portion of the casing 28, and a spring 35 normally presses it to its closed position. As long as the compressor is stopped or has not attained its normal speed, the weight 21 will be retained substantially in the position shown in Fig. 1. This position of the weight 21 holds the valve 29 open through the bell crank 211 and rod 27 above described. In this position of the valve 29, that is, open, receiver pressure is admitted through conduits 30 and 31 directly to the controlling devices such as shown at 32 or 33, thus preventing any compression taking place within the cylinder 10. As soon, however, asthe compressor approaches its predetermined or normal speed, the weight 21 will move outwardly and simultaneously slightly toward the pulley 12 so that the annular portion 2O will assume the position shown in Fig. 3. The spring 35 will then force the valve 29 to its closed position aft-er which no liuid will be admitted to the controlling devices 32 or 33 and the compressor will then start to compress tluid. Preferably and as shown in Fig. 3, the position of the annular portion 20 is such that during normal operation of the compressor the roller 26 does not contact with it. lf desired, a light spring 36 may be provided to support the weight of the bell crank as shown in Fig. 2. Also, in order to exhaust the fluid in conduit 31, a small leak port may be provided as in a valve shown at 38. ln this way, as soon as valve 29 closes, the fluid within conduit 31 will be slowly exhausted thus causing the relief valves 32 to close or the discharge pipe iinloader 33 to operate slowly.

lWhat l claim is:

1. A speed responsive device comprising in combination, a spring retained centrifugal element, a main driving shaft, a plurality of parallel pivotally mounted links obliquely disposed for attaching said element to t-he shaft whereby movement radially of said element moves said element a short distance axially of said shaft, means contacting with an integral portion of said centrifugal element and operated by the axial movement of said element to control a valve, and means to operate said valve when the centrifugal element moves away from its axis of rotation.

2. A speed responsive device comprising in combination, a spring retained centrifugal element, a main driving shaft, a plurality of obliquely disposed pivotally mounted links adapted to oscillate about parallel axes for attaching said centrifugal element to the shaft whereby movement radially of said centrifugal element moves said element a short distance axially of said shaft, means contacting with an integral portion of said centrifugal element surrounding said shaft and operated by the axial movement of said element to operate a valve, and means to control said valve when the centrifugal element moves away from its axis of rotation.-

3. A speed responsive device comprising in combination. a spring retained centrifugal element, a main driving shaft, a member thereon, a plurality of pivotally mounted the shaft whereby movement radially of said element moves saidelement a short distance axially of said shaft, and means contacting lwith an integral portion of said centrifugal element surrounding said shaftwhen the shaft is not rotating and operated by the axial movement of said element to control the operation of a valve during the starting of said main driving shaft and element.

4t. A speed responsive device comprising in combination, a centrifugal element, aI main driving shaft a. member thereon, an integral extension formed on said element having a fiat radial face substantially concentric with said shaft, a. plurality of parallel pivotally mounted and obliquely disposed links for attaching said element to said member on' the shaft whereby movement radially of said element move-s it simultaneously a short distance axially of said shaft, and means contacting with said element while the shaft is not rotating and operated by the movement of said element to control the movement of a valve during the starting of said shaft and element.

5. A speed responsive device comprising in combination, a centrifugal element, a main driving shaft, said element being mounted for simultaneous radial and axial movement relative to said shaft, a bell crank adjacent an integral portion of said centrifugal element surrounding said shaft and oscillated by movement of said centrifugal element axially of said shaft, a valve operated by movement of said bell crank, and

means to control said valve when the element is moved away from its axis of rotation.

6. A speed responsive device comprising` in combination, a centrifugal element, a main vdriving shaft, said element beingl mounted for simultaneous radial and axial movement relative thereto, a bell crank adjacent an integral portion of said centrifugal element surrounding said shaft cont-acting therewith when the sha lt is not rotating and oscillated by movement of said centrifuga element axially of said shaft, and a valve the operation of which is controlled by movement of said bell crank until the centrifugal element attains substantially its normal speed.

7. A speed responsive device comprising in combination, a centrifugal element, a main driving shaft, said element being mounted for simultaneous radial and axial movement relative to said shaft. a bell crank adjacent an integral portion of said centrifugal element surrounding the shaft and concentric therewith and oscillated by movement of said centrifugal element axially of said shaft, and means moved by said bell crank to operate a valve, said bell crank contacting with said centrifugal element` while the shaft is not rotating and being out of Contact therefrom after said centrifi ugal element has been moved axially and said shaft is rotating at approximately normal speed.

In testimony whereof, I hereto aiiix my signature.

WARD RAYMOND. 

